Late Ventricular Potentials in Cardiac and Extracardiac Diseases

Late ventricular potentials (LVPs) are low amplitude, high frequency waveforms, appearing in the terminal part of the QRS complex of the electrocardiogram (Barbosa et al, 2002; Olinic & Zdrenghea, 1998), generated by diseased myocardium. They may extend in the ST segment (Zimmermann et al, 1983). Late ventricular potentials may be also defined as fragmented electrical activity, appearing in heterogeneous tissue areas, located at the border zone of a myocardial infarction (Fetsch, 1999). They are markers of an electrophysiological substrate for reentry ventricular tachycardia (VT) and sudden cardiac death (SCD) (Zipes et al, 2006). Most of the clinical research in this field is focused on risk stratification of patients with a history of myocardial infarction (MI), but the role of LVPs in other cardiac and extracardiac diseases is also discussed. At present, there is considerable interest on improved tests for risk stratification of sudden cardiac death and appropriate selection of prophylactic implantable cardioverter defibrillator recipients.